1. Field of the Invention
This invention relates generally to a corner fastener for use in securing first and second sash members together and more particularly to a corner fastener which is utilized to secure skylight sash members together to form a sash for a skylight.
2. Description of the Prior Art
Corner locks are well known in the window and door industry. Corner locks are used to join and secure two members together Typically, the members have a 45.degree. mitre and when they are brought together, they for a 90.degree. corner. The corner lock functions not only to secure the two members together, but also to assist in aligning the members so that the members are properly aligned along their 45.degree. mitres so as to form a true 90.degree. angle when the members are secured to each other. The joint angles do not necessarily have to be 90.degree. . The joint angles could be 105.degree., 70.degree., 150.degree., etc. with corresponding mitre angles of one-half of the joint angle.
Typically, the corner index is off an outside surface of the frame and must rely on proper placement of the screw hole or friction fit for proper joining of the members There is usually no room for adjusting the mitre When using a friction fit it is difficult in assembly to do all of the force fitting of parts. Also, once fitted, you would have a questionable locking force to keep the lock from coming back out.
One example of an improved corner lock is seen in U.S. Application Ser. No. 321,730, filed Mar. 10, 1989. In that application, a corner lock is disclosed as having two leg members each with a threaded aperture Two screws are inserted through the frame and then into the leg members. As the screws are tightened, an offset in the leg members assists in aligning and adjusting the miters of the first and second frame members. While the corner lock described is also a non-friction type corner lock, it does have screws which go through the frame members. In certain instances, this may prove an aesthetic drawback. In addition, the operation of the corner lock is such that the tightening of the screw through the first leg causes movement of the second frame.
The present invention provides for an improved corner lock which is a non-friction corner lock and does not utilize holes which are drilled through the sash members.